This iris series is native to Europe's Mediterranean region, counting the Iberian Peninsula. Spuria irises belong to the apogon irises, which are beardless. These iris plants are conspicuous due to their attractive blooms having slender standards and falls. Their flowers bear a resemblance to the slender and elegant blooms of the bulbous irises. Today, botanists have identified more than a dozen of iris sub-species belonging to the Spuria iris series.
All plants belonging to the Spuria irises have their origin in the area around the Mediterranean Sea, extending from Spain to the northern regions of Africa. You can also find Spuria irises growing in fewer numbers towards the north, as far as Denmark and eastern England. Some plant can also be found growing in farther places in the east like Russia, Afghanistan and the western provinces of China. Sir Michael Foster was the first to introduce Spuria irises into England towards the end of the 19th century. He is well known for introducing a hybrid iris named "Monspur", which turned out to be important to hybridizers working on Spuria irises. However, it was only in the 1920s that iris hybridizers started developing serious programs with a view to enhance the quality of Spuria irises for growing in home gardens. The first American to breed Spuria irises was T. A. Washington, who incorporated "Monspur" and other iris species in the hybridizing programs undertaken by him. Most of the Spuria hybrids developed by Washington inherited a particular trait from the "Monspur" and the iris species called Iris halophila - summer-green foliage. Iris hybridizers in the US are credited with developing several wonderful Spuria cultivars whose blooms come in an assortment of hues. In fact, these hybridizers have been the leaders in breeding programs involving Spuria irises. Although most programs related to growing as well as breeding Spuria irises are concentrated in the Southwest United States and California, where the climatic conditions are sun-drenched and warm, these days, more and more Spuria lovers and growers from other places such as Texas and Missouri and also other states like Montana and Minnesota are taking keen interest in Spuria breeding. In fact, several other iris growers in Europe, Australia and New Zealand have also been infected by the Spuria "bug" recently.
The flowering season of Spuria irises begins a couple of weeks after the tall bearded irises have completed flowering. Different from the tall bearded irises, whose flowers as well as stalks break quite easily, those of Spuria irises are quite tough. In fact, Spuria iris blooms are excellent for any floral arrangements, as the flowers remain fresh for about three to four days together. To use them for floral arrangements, you need to cut the flowering spikes immediately when the buds start showing their color. Spuria irises are one of the tallest irises and nearly all species grow up to a height of anything between 3 feet and 4 feet (90 cm and 120 cm), provided they are grown in favourable conditions. Occasionally, some Spuria iris plants may be found growing up to a height of 5 feet (150 cm) or more. Ideally, the flowering spikes of this iris series should bear no less than two buds in the terminal of each branch. It is very common to see Spuria irises producing three or four buds on each stalk, particularly on plants that have large blooms. While some stalks may produce as many as seven buds, it is not too often. Spuria flowering stalks have curvy or bending branches. The leaves are leathery, while the rhizomes are woody. The roots of Spuria irises are wiry - a typical feature of plants belonging to this iris class. Several spuria cultivars become dormant during the summer. In fact, the growth of these plants stops when the summer months become hot. As they enter a dormant phase in summer, growers do not require watering the plants to make up for the inadequate rainfall during summer. Some Spuria irises, counting the one called "Belise", are categorized as summer-green, as these plants do not become dormant even during the summer. On the contrary, they remain green and their growth continues despite the summer heat. However, you may need to provide the summer-green varieties with additional water if the rains during summer do not offer much moisture. The number of chromosomes of different Spuria iris species varies considerably. Sometimes the difference is so great that it is possible to hybridize several spuria species. The number of chromosomes differ from diploids (original Spuria iris species having the original chromosome count) having a 2n of 16 to a much higher count of 72. It is very surprising to note that the dwarf spuria species have the highest chromosome count! In addition, it has been found that some normal tetraploid spuria irises have double the number of the regular chromosome count - an attribute that is important for substance, larger size as well as robustness. The current trend in hybridization of Spuria iris is toward smaller plants and small flowers having broader petals as well as flowers with no signals - the colored spots that emerge in the same place of the flowers where the beards of bearded irises grow. Although the blooms of Spuria irises are excellent as cut flowers, they are yet to be widely used by flower arrangers. In addition, as the flowers remain fresh for three to four days, they practically prolong the flowering season of this iris series and also highlight the places in the garden where they are grown. Hybridizers have developed a variety of spuria iris cultivars that come in different colors and patterns, counting halos, bitones and bicolors.
When compared to the tall bearded irises, spuria irises possess the ability to draw in additional water as well as fertilizer. Iris growers in the southwest regions of United States need to stop the water supply to their Spuria irises and allow them to become dormant during the hot summer months. This should be done after the plants have completed flowering and the summer heat starts increasing. However, Spuria irises grown in farther north as well as in places receiving summer rains, the plants will remain green and continue to grow throughout the summer. If you are planning to grow Spuria irises, you need to dig a planting hole measuring 12 inches X 12 inches X 18 inches and combine about two gallon compost into it. In addition, mix some slow-release fertilizer together with some super phosphate. The rhizomes of Spuria irises should be planted one inch deeper than those of the tall bearded irises in wet spots that are well-drained. In fact, the tall bearded irises will not thrive in such conditions. It is important to ensure that you do not provide the plants with excessive water when the humidity is high or during heavy rains. Ensuring this will help protect the plants from mustard-seed fungus, their main enemy. Compound barnyard manures are the best fertilizers for Spuria irises, which are heavy feeders. In case you cannot avail manure, you may also use commercial fertilizer like 10-20-10 or 10-10-10. Like in the case of majority of the beardless irises, you should plant Spuria irises during fall and subsequently provide them with a heavy mulch to protect the plants from the harsh winter during the first year of their existence. This is especially important for growers in places where the temperatures drop below the freezing point in winter. The two issues vital for successfully growing Spuria irises include a spot receiving full sunlight and an organic soil that never dries up completely. The fertility of the soil will have a significant influence of the number as well as the size of flowers produced by Spuria irises. It is also important to ensure that the vicinity of Spuria irises is kept free from weeds. Weeds combined with high temperature and moisture may result in your plants suffering from some common diseases that they are vulnerable to, including the fungal disease called Southern blight. In the northern regions as well as the Midwest, Spuria irises may also be troubled by iris borers. Therefore, the growers in these places should ensure that they clear the withered flowers and old foliage regularly. You can lift and divide the spuria irises either during fall or in early spring. While dividing the rhizomes, ensure that they do not dry out. Usually, Spuria irises grow to a relatively short height in the first year following the division and replanting of their rhizomes. If you are dealing with larger Spuria iris plants, the difference in their height in the first year after transplanting and that in the successive years is about one foot or a little more. It has been established that if your store Spuria iris rhizomes in a refrigerator prior to dividing and replanting them, they will not only have a rapid growth, but also bloom earlier. Spuria irises can be propagated quite easily from their seeds, which germinate readily. In fact, the germination is better when the seeds are sown soon after the pods begin to split open. When grown in favourable conditions and provided they are planted near the beginning of the growing season, Spuria iris seedlings will start blooming from the second year since they are planted. If you do not wish to gather the seeds, ensure that you cut the withered blooms to prevent the plant from using its energy to produce seeds. In case you do not plan or take out time for cross-pollination, the seeds produced under normal circumstances will be through open pollination facilitated by bees as well as other insects. As far as propagating new plants is concerned, these types of seeds do not have much value, as they do not produce true varieties.
The flowers of Spuria irises bear a resemblance to those of the Spanish (Xiphium) and Dutch irises, which are generally available from the florists' shops. Similar to the Xiphium irises, the blooms of Spuria irises also make wonderful cut flowers. Often, two or even more flowers of Spuria irises open simultaneously on tall, generally branchless stalks. Spuria irises come to bloom in the beginning of summer - the period when the tall bearded irises are also in bloom. The flowers of this iris class have strong hues and, hence, are conspicuous in the midst of the foliage. The blooms of Spuria irises have an atypical individual feature - even after the flowers desiccate, three nectar drops remain at the base of their falls (haft) as well as the standards. Majority of the tall contemporary Spuria irises are developed by crossing Iris crocea and Iris orientalis.